Mechanical Pulverization of Co-Free Nickel-Rich Cathodes for Improved High-Voltage Cycling of Lithium-Ion Batteries

Abstract

Nickel-rich cathode materials are quickly becoming the next commercial cathode for electric vehicles; however, their long-term cycle life retention and air stability remain a barrier to the use of these lower-cost, higher-energy density materials. Surface reactivity and mechanical degradation, especially at high voltages, remain two issues that impede these material’s commercialization. While surface treatments have shown great promise in reducing surface reactivity, mechanical degradation or “cathode cracking” persists yet. In the present work, LiNi0.9Mn0.05Al0.05O2 (NMA) cathode materials are first pulverized into their primary particle constituents and then coated with lithium phosphate via solution-based chemistry with varying concentrations of phosphoric acid. The cathodes are characterized using energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, electrochemical impedance spectroscopy, and electrochemical cycling. After 100 cycles, the pulverized NMA cathodes coated using the lowest concentration of phosphoric acid show delayed voltage decay and double the discharge capacity compared to the pristine material in full cells during high-voltage cycling.

Scope and significance of transition metal oxide nanomaterials for next-generation Li-ion batteries

“…Previously, it was shown that ball-milling microparticles to morphed oval/ellipse/spherical particles could increase the tap density. 6 The reason is that the spherical shape group of particles tends to occupy more volume, thus increasing the tap density and the system's cathode level energy density. 100 Optimizing any of the mentioned synthesis methods in this work or discovering a new creative synthesis route that can produce spherical nanomaterials can be a potential development toward the commercial pathway for nanomaterials.…”

“…9,77,96,97 Nanomaterials (NM) have the advantage of being grown into a monodisperse, single-crystal morphology from the bottom-up by arranging the atoms perfectly or deconstructing microparticles by applying external energy. 98,99 Researchers can synthesize S.C. materials for cathode materials at higher calcination temperatures utilizing existing precursor morphology. 16,53 This creates a very vague boundary to distinguish N.M. and S.C. materials.…”

“…The advanced materials consisted of several morphological feats contributing to the commercial value by decreasing the production cost, reducing the use of high-cost minerals, and adapting to low-cost fabrication techniques. [3][4][5][6][7] Some examples include the core-shell material, concentration gradient, full-concentration gradient material, graingrowth aligned/oriented materials, and potential nanomaterials. 8 Nanomaterials are materials with either one of the 3D dimensions in the dimensional space in the nanoscale regime o1000 nm or 1 mm.…”

Materials Towards the Development of Li Rechargeable Thin Film Battery

“…As a matter of fact, efforts are being made towards the understanding the role of Co ions in layered structures (Voronina et al, 2020;Liu et al, 2021d;Gent et al, 2022;Shen et al, 2022a), so that suitable ions for replacement of Co ions may be identified . Considering, abundance and high price of Co (Brow et al, 2022), various research groups around the world are working towards designing Co free Ni rich layered oxide cathode by looking for a suitable ion to replace Co (Mu et 2022;.…”

H2O/HF Scavenging Mechanism in Cellulose-Based Separators for Lithium-Ion Batteries with Enhanced Cycle Life

“…The useful life of a battery is directly related to its capacity fade (a loss in capacity upon cycling or aging), which can result from several interconnected mechanisms that lead to increased cell resistance, loss of active material, and/or loss of lithium inventory. 4,8,9 In modern LIB technology, capacity fade is partially governed by the dissolution of transition metals inside the cathode. 10,11 This dissolution is caused by an oxidation reaction when the transition metal surface is exposed to hydrofluoric acid (HF).…”